George F. Thomas says, concerning the point of Jesus’ parable of the Prodigal Son,
[...] The older brother represents the principle of merit and justice and quite properly complains that his younger brother’s reckless conduct has not deserved the love shown him by his father. [Citation omitted] Thus, God’s love is not measured out according to the value of the person loved, as human love is; rather, God is the Creator and His love is creative of worth. Even the sinner has some worth as a creature made in the image of God; and God’s love is “creative,” not in the sense that it gives value to a being that is wholly without value, but that it brings to fulfillment possibilities of value that were present but frustrated.
Though God’s love is given us irrespective of our actual worth, it is effective in our lives only when we respond to it in the right way. For example, Jesus makes it clear that the forgiveness of our sins is conditional upon our willingness to forgive others. Moreover, we are commanded in the Gospels to love our neighbor and are told in the First Epistle of John that the test of our love of God is our love of our neighbor. In other words, God’s love is given to us whether we deserve it or not; but it is given with the purpose of awakening in us the desire and capacity to love Him and our neighbor. Hence, we must regard ourselves not as passive recipients of God’s love but as active and responsible beings called by God to cooperate with Him in the achievement of His purpose of love in our own lives and in the lives of others.
--George F. Thomas, pp. 51-2 of Christian Ethics and Moral Philosophy, Charles Scribner’s Sons New York, 1955.Thus, God does not love us from the need of anything we can give Him in return; but He loves us with the purpose that we should return His love and thus enter into communion with Him by giving ourselves to Him. His agape-love moves downward to us, but it seeks to start in us a reciprocal movement upwards towards Him. Similarly, we are to love our neighbor without regard to his worth or his return of our love; but we are to strive through our love to awaken in him the capacity to give as well as receive love and thus to help him realize his potential worth. The result may be that our giving to him will be met by his giving to us, and a fellowship of mutual giving and receiving will be established between us.